In farming applications, chemical applicators are sometimes used to apply one or more chemicals to material being conveyed, such as seed being conveyed from a seed tender or from a grain cart. For example, graphite and talc are often used as dry lubricants for seed moving and planting operations. Talc operates as a dry lubricant when it is applied to seeds, but another primary role for talc is as a drying agent. Seed is subjected to air flows and ambient humidity when being moved within the farming equipment, and the seed itself as well as any pesticide coatings on the seed can pick up moisture from the ambient air during this process. That pickup of moisture can lead to additional friction and potential sticking/clumping points or jams within the equipment in the absence of the drying provided by chemicals such as talc. The problems with clumping and bridging of material is also present in some circumstances thanks to static electricity that sometimes builds up in the conveyor systems. To this end, the talc effectively smooths and dries the surface of seed to help avoid problems with clumping and/or bridging of material that may otherwise happen because of moisture in the environment.
Of course, the addition of talc to seed should be tailored such that enough talc is added to help prevent the potential flow problems described above, but not an excessive amount which will just be wasted by blowing into the atmosphere rather than coating the seed. Accordingly, talc applicators should typically be designed to carefully meter out flow of talc based on the movement of seed in the associated farming equipment. Many conventional talc applicators are designed to dispense talc at a constant, controlled rate, but this type of arrangement cannot account for variations in seed movement rate. More recent systems in this field have added variable speed drive mechanisms to address this problem of varying seed conveyance or application rates, but this adds potential complexities and added costs to the system.
Regardless of the design of the talc applicator, one further technical problem that must be addressed is the packing of the talc within the storage hopper of the talc applicator. Chemicals such as talc are typically not free flowing, which means the particles of the talc exhibit self-adherence qualities that can prevent an auger or another dispensing element from receiving a flow of talc to dispense to the seed tender, grain cart, or the like. As such, an agitator must typically be provided within the storage hopper to avoid blockages caused by the non-free flowing nature of chemicals such as talc. This agitator is typically another element like the dispensing element which must be powered with input energy, and these elements can add significant complexity and potential failure points within the talc applicator. These issues can be exacerbated when ambient conditions have high humidity.
There is a need, therefore, for further improvements in the field of chemical applicators such as talc applicators, which address these and other deficiencies of known designs.